Mapping and assessing ecosystem services for sustainable policy and decision-making in Eritrea

The mapping and assessment of ecosystems and their services (MAES) is key to inform sustainable policy and decision-making at national and sub-national levels. Responding to the paucity of research in sub-Saharan Africa, we conduct a pilot study for Eritrea that aims to map and assess the temporal dynamics of key ecosystems and their services. We reviewed policy and legal documents, analyzed land cover changes and estimated the potential for ecosystem services supply through an expert-based matrix approach. Our results showed that from 2015 to 2019, the potential supply of the ecosystem services analyzed (e.g., crop provisioning, water supply and recreation) increased, with the exception of wood supply. Overall, our study presents policy-relevant insights as to where to conserve, develop, or restore ecosystem services supply in Eritrea. Our approach is transferable to similar data scarce contexts and can thereby support policies toward more sustainable land development for people and nature. Supplementary Information The online version contains supplementary material available at 10.1007/s13280-023-01841-4.


ES Definition a) Crop
Ecosystem contributions to the growth of cultivated plants that are harvested for various uses including food and fibre production, fodder and energy. b) Grazed biomass the ecosystem contributions to the growth of grazed biomass that is an input to the growth of cultivated livestock (excluding the growth of crops used to produce fodder for livestock) c) Wood ecosystem contributions to the growth of trees and other woody biomass, both cultivated and uncultivated, that are harvested for various uses including timber production and energy..

d) Water supply
combined ecosystem contributions of water flow regulation, water purification, and other ES to the supply of water of appropriate quality to users for various uses including household consumption.

e) Global climate regulation
Global climate regulation services are the ecosystem contributions to the regulation of the chemical composition of the atmosphere and oceans that affect global climate through the accumulation and retention of carbon and other GHG (e.g., methane) in ecosystems and the ability of ecosystems to remove carbon from the atmosphere. This is a final ES.

f) Soil erosion control services
Soil erosion control services are the ecosystem contributions, particularly the stabilising effects of vegetation, that reduce the loss of soil (and sediment) and support use of the environment (e.g., agricultural activity, water supply). This is may be recorded as a final or intermediate service.

g) Pollination
Pollination services are the ecosystem contributions by wild pollinators to the fertilization of crops that maintains or increases the abundance and/or diversity of other species that economic units use or enjoy. This may be recorded as a final or intermediate service.

h) Nursery population and habitat
Nursery population and habitat maintenance services are the ecosystem contributions necessary for sustaining populations of species that economic units ultimately use or enjoy either through the maintenance of habitats (e.g., for nurseries or migration) or the protection of natural gene pools. This service is an intermediate service and may input to a number of different final ES including biomass provision and recreation-related services.

i) Recreationrelated
Recreation-related services are the ecosystem contributions, in particular through the biophysical characteristics and qualities of ecosystems, that enable people to use and enjoy the environment through direct, in-situ, physical and experiential interactions with the environment. This includes services to both locals and non-locals (i.e. visitors and tourists). Recreation-related services may also be supplied to those undertaking recreational fishing and hunting. This is a final ES.

j) Spiritual, artistic and symbolic
Spiritual artistic and symbolic services are the ecosystem contributions, in particular through the biophysical characteristics and qualities of ecosystems, that are recognized by people for their cultural, historical, aesthetic, sacred or religious significance. These services may underpin people's cultural identity and may inspire people to express themselves through various artistic media. This is a final ES.
Section 2 -Land use changes: regional and sub-regional statistics

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Section 3 -ES mapping and assessment      In the following, three MAES-relevant ongoing initiative in Eritrea. The selected of examples refer to both the national and regional level; we thus want to highlight some of their impacts as well as possible links with a MAES application such as the one proposed in this study. The examples represent a good starting point for exploring potential causal links between identified ecosystem changes and current policies, and projects implemented on the ground, possibly involving key actors dealing with biodiversity and ES issues in the country. By way of example, Box 1 offers some insights considering some large dam project as well as protected areas.

Example 1 Greening Campaigns to restore Ecosystems in Eritrea
Since 1991, the Government of Eritrea (GoE) has taken initiatives to enhance the country's biodiversity by adopting mechanisms and mobilizing communities and resources. These activities are now undertaken by the Forest and Wildlife Authority (FWA). Overall, the impact of all the ecosystem restoration initiatives is significant. Among other things, 132 million trees have been planted in the last 29 years, or an average of 4.6 million trees per year. In addition, the FWA has established a total of 396,930 hectares of protected area, out of about two million hectares planned to be enclosed in the future, to promote natural regeneration of trees and grasses. The enclosures have flourished in biodiversity and many endangered wildlife are returning to the habitat while new ones are emerging. In all this, the participation of people from all walks of life, especially members of the defense forces, students and local communities, in afforestation and reforestation programs has been crucial. Notably, more than 500 Green Clubs have been established across; yet, only 50% of the planned number of clubs have been created. This is also indicative of the arduous challenges ahead.

Example 2 Maekel Region: Success in Reforestation
According to Wildlife and Forestry Authority in the Maekel region, reforestation activities have been taken place for over 28 year, with the involvement of all sectors of society, including students participating in Summer Work Programs. Of note, through it four major, and five smaller nurseries, the region has been provided 1 million seedlings every year. These include eucalyptus and Indigenous tree species, the former being the most widely preferred tree in the highlands (by the inhabitants) because it grows fast and has big demand in the construction sector. The region can serve as a living lab to advance MAES application in the country and thus contribute to the ambitious greening campaign in the country.